Apparatus for drying sawdust.



H. C. JOHN SON. APPARATUS FOR DRYING SAWDUST.

APPLICATION FILED JAN. H. 1915- Patented Nov. 30, 1915.

2 $HEE TSSHEET 1.

A? /flW WITNESSES 4Z$ A TTORNEVS H. C. JOHNSON. APPARATUS FOR DRYING SAWDUST.

APPLICATION FILED JAN 11. ms.

Patented Nwso, 1915.

2 SHEETS-SHEET 2- WITNESSES A TTOH/VEYS COLUMBIA PLANDURAPH c0., WASHINGTON, n. c.

UNTTE BTA.

' HANS C. JOHNSON, OF FORT BRAGG, CALIFORNIA.

APPARATUS FOR DRYING SAWDUST.

Specification of Letters Patent.

Patented Nov. 36, 1915.

Application filed January 11, 1915. "Serial No. 1,547.

To all whom it may concern:

Be it known that I, I-IANs C. JOHNSON, a citizen of the United States, and a resident of Fort Bragg, in the county of Mendocino and State of California, have invented a new and useful Improvement in Apparatus for Drying Sawdust, of which the following isa specification.

My invention is an improvement in apparatus for drying sawdust, and has for its object to provide a device of the character specified, having mechanism for taking the waste sawdust of a saw mill, thoroughly drying the dust, removing splinters and other foreign bodies, and delivering it finally in condition for packing fruit and like products.

In the drawings :Figure 1 is a side view of the apparatus with parts in section, Figs. 2' and 4: are sections on the lines 22 and 4 1, respectively, of Fig. 1, and Fig. 3 is a detail sectional view of the connection between a pair of driers.

The improved apparatus consists essentially of a series of drying mechanisms, having means for feeding'the sawdust and for drying it during its travel, and screening mechanism for separating the dried sawdust from the foreign bodies.

The drying mechanism consists of a se ries of cylinders, three in the present in stance, and designated A, B and C, respectively, arranged one above the other in parallel relation, and all of the cylinders incline upwardly slightly from the feeding to the delivery end.

Each cylinder as shown, consists of a number of sections 1 of tubular form arranged in alinement, and connected at their meeting ends by couplings 2. The cylinder A is provided at each end with a head 3 and 1, respectively, and the head 3 has a hopper feed 5 at its upper side for permitting the sawdust to be fed to the cylinder. The cylinder B is provided at the end remote from the head 3 of the cylinder A with a head 6, and there is a connection 7 between the adjacent heads 4 and 6.

The cylinder C is provided at each end with a head 8 and 9, respectively, and the head 8 has a receiving hopper l0, corresponding in position and arrangement to the hopper 5 of the head 3. Ihe head 9 of the cylinder C is provided with an outlet 10, which delivers to a head 11 on a fourth cylinder D, the said cylinder being coniposed of tubular sections 12, arranged in alinement, and connected by couplings 13, corresponding to the couplers 2 of the cylinders A, B and C.

In each of the four cylinders A, B, C and D there is journaled a shaft 1 1, the shaft being jc-urnaled in bearings 15 in the ends of the heads, and to each shaft is secured a spiral blade or vane 16, the said blade or vane extending practically the full length of the cylinder. The upper or delivery end of the cylinder A delivers to the upper or inlet end of the cylinder B and the lower delivery end of the cylinder B delivers to a cylindrical screen 17, which is secured to an extension of the shaft 14:, which carries the blade 16. This screen is as before stated, cylindrical, and of larger diameter than the cylinder B, and is arranged coaxial with the said cylinder and with the delivery end of the cylinder extending into the inner end of the said screen. Both ends of the screen are open and the delivery end thereof delivers to the hopper 10.

The upper or delivery end of the cylinder C delivers to the lower or inlet end of the cylinder D, and this cylinder D has its lower end below the lowest end of the cylinder C and thence inclines upwardly to a point above the three cylinders A, B and C. At its upper end the cylinder D is provided with a head 18, having an outlet 19, which delivers to one end of a cylindrical screen. This screen consists of two portions 20 and 21, arranged coaxial and secured to a common shaft 22, which is journaled in suitable bearings 23. A screen 2021 is arranged in inclined position, inclining in the opposite direction to the cylinder D and with the portion 20 at the upper or inlet end of the screen.

A waste chute 2 1 is arranged beneath the portion 20 of the screen, in such manner that any material passing through the screen will be delivered to the chute and will be delivered by the chute away from the drier. The portion 20 of the cylindrical screen is of finer mesh than the portion 21, and is also of greater length, and the material passing from the drier D is delivered to this portion 20.

The portion 21 of the screen is provided at its lower end with a delivery chute 24s for the waste material, and the material that passes through the meshes of the screen portion 21 fall upon the upper run of an endupper end of the shaft 14 of less belt 25, which is supported by rollers 26, journaled transversely of the ends of a supporting frame 27. The belt '25 is inclined and at its lower end this belt delivers to a s cond endless belt supported by rollers 29, journaled transversely of a supporting frame 30.

The belts and 28 are in inclined position, and the lower end of the upper belt overlaps the upper end of the lower belt. At its lower end the frame 30 is provided with a discharge chute 31. The outer faces f the belts 25 and 28 are provided with adhesive material that will cause the slivers and other foreign bodies in the sawdust to stick to the belts, and acleaning brush is provided in connection with each belt.

A shaft 32 is journaled in rear of the supporting frame. 27 and a similar shaft 33 is journaled in. rear of the supporting frame 30. Each of the shafts 32 and 33 is'provided with a cylindrical brush 34 and 35, respectively, of any suitable material, and

.the tips of the bristles of the brush engage the outer surface of the adjacent belt on the under or rear run thereof to clean the slivers and other foreign bodies from the belts. The shaft 14 of the drier cylinder 4 is extended beyond the head 3, and a driving shaft 36 is connected to the extension, by means of a universal joint 27. A driving shaft 38 is connected to the shaft 14 of the drier cylinder B by means of a universal joint 39, and a shaft 40 is connected to the shaft 14 of the drier cylinder C by a universal joint 41. All of the driving shafts 36, 38 and 40 are at the same end of the drier cylinder, that is, at the inner end of the cylinder A.

A driving shaft 42 is connected to the the drier D by a universal joint 43, and a driving shaft 44 is connected to the lower end of the shaft 22, by means of a universal joint 45. Pulleys 46 are connected to the uppermost rollers 26 and 29 of the belts, and pulleys 47 are connected to the ends of the shafts 32 and 33 of the brushes. the drier cylinders, the belts, the brushes and the screen shaft 23 may be driven from the driving shafts from any suitable source of power.

It will be noted that each of the cylinders A, B, C and D has a double wall or jacketed cylinder, and means is provided for circulating a heating fluid through the double.

wall or jacket. Each cylinder has an outlet pipe 48 at the end adjacent to the feed hopper of the cylinder A, and an inlet pipe 49 at the opposite end. Each of the inlet pipes is on the upper side of the cylinder and each of the outlet pipes is on the under side.

In operation the material to be dried is fed into the drier cylinder A by way of Thus all of the shafts 14 ofthe feed hopper 5, it being understood that the shafts 14 of all of the driers, the shaft 22 of the screen 20-2l, and the shafts of the belts 25 and 28 are in motion. The endless conveyer constituted by the shaft 14 and the spiral blade 16 moves the sawdust toward the upper end of the drier cylinder, and as it travels it is dried, that is, the moisture is evaporated by the heated air or steam that is supplied to the jacket of the cylinder.

At the upper end of the cylinder A the sawdust is fed to the cylinder B and travels down this cylinder, being finallv. delivered into the screen 17. Here the finest dust is screened out, and is deliveredaway from the machine by means of'a chute 50. The V upper end of the cylinder" and delivers it finally through thechute 23 into the portion 20 of the screen 2021. Here the finer dust is screened out passing through the meshes of the screen portion 20 into the delivery chute The coarse dust passes into the screen portion 21, and again this dust is screened, that suitable for packing fruit beingdelivered through the meshes of the screen, While that unsuitable for such purpose is delivered through the Waste chute 4.

That portion of the sawdust suitable for packing falls upon the/upper face of the upper. run of the endless belt 25 and rolls down over this belt on to the upper face of the upper run of the belt 28. What slivers or fine dust that may have been re tained in the sawdust is here removed adhering to the adhesive material on the outer face of the belt and as this fine dust, slivers, and the like, passes beneath the brushes in rear of the belts such material is removed, leaving the belts in condition for taking up more of the said material. I

.The apparatus removes all of the'fine dust, and all splinters, slivers or. foreign inders and two screens, it is obvious that a greater or less number of cylinders or screens might be used, and that they might lVhileI a complete Inabe diiferently arranged to attain the same 7 purpose. Neither is it absolutely necessary to incline the cylinders, the upward inclination being for the purpose of slowing the feed to permit a longer time for drying. While the screen 2.0-21 is cylindrical for convenience, it is obvious that it might have other forms. r

The endless belts 25 and 28 are not conveyers, being in fact separators for separating the fine dust, slivers, splinters, and foreign bodies from the saw dust. These materials will adhere to the belt. The prepared sawdust will be delivered by the end less belts 25 and 28 through the chute 31 to a suitable receiver. The inclination of the cylinders is also for the purpose of giving head room for the discharge chute end and hopper 10 of the cylinder D, and to give the proper inclination to the screen 17 1. An apparatus for drying sawdust, comprising a series of substantially parallel drying cylinders arranged one above the other in spaced relation, and inclining upwardly toward one end, the uppermost cylinder having a feed hopper at its lower end and having a connection with the succeeding cylinder at its upper end, a shaft journaled axially of each cylinder and provided with a spiral vane or blade for conveying the sawdust through the cylinder, each cylinder having a double wall and having an inlet at one end and an outlet at the other for permitting the circulation of a heating medium between the walls, a cylindrical screen secured to the shaft of the intermediate cylinder at the lower end thereof, and coaxial with the cylinder and of greater diameter, the cylinder delivering to the upper end of the screen, and said screen having an outlet chute at its lower end, the lowermost cylinder having a hopper to which the chute delivers, a waste chute below the screen, screening mechanism arranged above the lower ends of the series of cylinders, and an inclined drier cylinder to which the lower of the first-named cylinders delivers at the lower end of the lastnamed cylinder, said last-named cylinder delivering to the screening mechanism at its upper end, and the said cylinder having con- I veying mechanism for conveying the sawdust from the series of cylinders to the screening mechanism.

2. An apparatus for drying sawdust, comprising a series of substantially parallel drying cylinders arranged one above the other in spaced relation, and inclining upwardly toward one end, the uppermost cylinder having a feed hopper at its lower end and having a connection with the succeeding cylinder at its upper end, a shaft journaled axially of each cylinder and provided with a spiral vane or blade for conveying the sawdust through the cylinder, a cylindrical screen secured to the shaft of the intermediate cylinder at the lower end thereof, and

coaxial with the cylinder and of greater diameter, the cylinder delivering to the upper end of the screen, and said screen having an outlet-chute at its lower end, the lowermost cylinder having a hopper to which the chute delivers, a waste chute below the screen, screening mechanism aranged above the lower ends of the series of cylinders, and an inclined drier cylinder to which the lower of the first-named cylinders delivers at the lower end of the lastnamed cylinder, said last-named cylinder delivering to the screening mechanism at its upper end, and the said cylinder having eonveying mechanism for conveying the sawdust from the series of cylinders to the screen mechanism.

3; An apparatus for drying sawdust, comprising a series of drying cylinders arranged one above the other and approximately parallel and having one end at a higher level than the other end, the uppermost cylinder having a feed hopper at its lowermost end, and delivering to the intermediate cylinder at its upper end, a screen to which the intermediate cylinder delivers at its lower end, said screen delivering to the lowermost cylinder, a conveyer in each drying cylinder for conveying the sawdust longitudinally thereof, screening mechanism arranged adjacent to the cylinders and at a higher level, and a drier cylinder receiving from the delivery end of the lowermost cylinder of the series and delivering to the screening mechanism, said drier cylinder having a conveyer therein for moving the sawdust.

4. An apparatus for drying sawdust, comprising a series of drying cylinders arranged one above the other and approximately parallel and having one end at a higher level than the other end, the uppermost cylinder having a feed hopper at its lowermost end, and delivering to the intermediate cylinder at its upper end, a screen to which the interniediate cylinder delivers at its lower end, the intermediate cylinder delivering to the lowermost cylinder at the opposite end from its connection with the uppermost cylinder, a conveyer in each drying cylinder for conveying the sawdust longitudinally thereof, screening mechanism arranged adjacent to the cylinders and at a higher level, and a drier cylinder receiving from the delivery end of the lowermost cylinder of the series and delivering to the screen mechanism, said drier cylinder having a conveyer therein for moving the sawdust.

5. An apparatus for drying sawdust, comprising a series of superposed drying cylinders, a conveyer in each cylinder for conveying the sawdust through the cylinders, the uppermost cylinder having a feed opening at one end and each cylinder delivering to the next lower cylinder at the opposite end from where the sawdust enters the cylinder, screening mechanism arranged adjacent to the cylinders and at a higher level, a drier cylinder having its inlet connected with the delivery end of the lowermost cylinder of the series and having its outlet end delivering to the screening mechanism, a conveyer in the said cylinder, and screening mechanism interposed between the lower cylinder of the series and the next uppermost for screening the sawdust as it is delivered from the said last-named to the first-named cylinder.

6. An apparatus for drying sawdust, comprisinga series of superposed drying cylinders, a conveyer in each cylinder for conveying the sawdust through the cylinders,

ing to the next lower cylinder at the opposite end from where the sawdust'enters the cylinder, screening mechanism arranged adjacent to the cylinders and at a higher level, a drier cylinder having its inlet connected with the delivery end. of thelowermost cyl inder of the series, and having its outlet end delivering to the'screen mechanism, and a conveyer in the saidcylinder.

HANS C.'J.OHNSONQ \Vitnesses J. K. PEIRSOL, J. K. PEIRSOL, Jr.

Copies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents,

Wash ngton, D. C. r 

